Tuesday, 10 November 2015

Royal Spoonbills

The Royal Spoonbill (Platalea regia) to my mind, and as the species name suggests, is a regal bird with brilliant white plumage and starkly contrasting black face, bill and legs. They are especially elegant in breeding condition when their heads are adorned with white nuptial plumes.

Portrait of a regal bird.
The Royal Spoonbill is moderately common in coastal and near coastal wetlands in Gippsland where birds may be found singly, in pairs, or in small parties and less often in large flocks. From my experience in East Gippsland a large flock would typically contain between 20 and 30 birds, larger flocks up to 50 or 60 birds are rare.

There are few breeding records for Royal Spoonbills in East Gippsland, for example “The Atlas of Australian Birds” and the “New Atlas” show no breeding records in East Gippsland for this species or for Yellow Spoonbills.

For a number of years now I have been observing Royal Spoonbills in small numbers roosting on the edge of the very large Ibis rookery in Macleod Morass near Bairnsdale and speculating that the Spoonbills may be breeding. This season there have been a larger than usual number of Royals on the edge of the rookery for an extended time so I decided to take a closer look and see if I could confirm breeding.

Part of the Ibis rookery in Macleod Morass.
The Ibis build colonial nest sites by breaking down Giant Rush (Juncus ingens) reed stems to form platforms. The rookery is moved each year to a new location. The Ibis do not nest in Common Reed (Phragmites australis) and Cumbungi (Typha orientalis), the other two dominant aquatic plant stands found in Macleod Morass.

Royal Spoonbills on the far side of the Ibis rookery.

The Ibis rookery contains mostly Straw-necked Ibis (Threskiornis spinicollis) and a smaller number of White (aka Sacred) Ibis (Threskiornis molucca). The Straw-necked outnumber the White by about 4 to 1.

A typical - though a more isolated - example of an ibis breeding platform on Giant Rush.

 As I walked by a row of large Red Gums a short distance from the rookery at least 20 Whistling Kites and a pair of Swamp Harriers flew out. These and other raptors such as White-bellied Sea-Eagles, have been feeding on Ibis chicks and no doubt earlier on eggs, for the duration of the Ibis breeding event. The chick and egg carnage is quite high, however as there are thousands of Ibis, a majority of young birds successfully reach adulthood.

Close up of a vacated nest platform showing the remains of a number of Ibis chicks - in the wild survival of the fittest rules.

 The Ibis young are now well advanced and have retreated from the more isolated margins of the rookery to form crèches. Adult Ibis continually come and go from the rookery on food gathering forays to the surrounding farm land. Excellent fliers, they are capable of travelling long distances to gather food for their young.

A dozen Straw-necked Ibis have been visiting our paddocks daily for over a month now making a return trip of 28 kilometres from the rookery many times each day.

Young Straw-necked Ibis gathered into a crèche.

In all, I counted 50 Royal Spoonbills at the rookery and I estimate there may have been up to another 10 birds out of sight giving a possible total of 60 birds and more may have been away feeding. As mentioned above, 50 or 60 Royal Spoonbills in a loose flock is from my experience a large gathering of this species in our area. All the spoonbills have nuptial plumes. Seven birds looked to be sitting on nests with two birds out on their own and the others located within the main flock of Royals on the edge of a large section of the Ibis rookery.

Approaching the rookery, I was mindful of not disturbing the Ibis and Spoonbills so I waded very slowly in stages in order to get close enough to the Royals for observation and some photos.  

The Royals appeared to prefer to construct nests in Giant Rush that is not been packed down into a low platform as the Ibis do.  

One of two Spoonbills on a suspected nest isolated from the main flock.

As I photographed a bird on one of the two isolated nests the bird departed giving me a brief chance to check the nest to see if there were eggs or chicks and thereby confirm for sure that the Royals are breeding. Royals typically lay 2 or 3 eggs.

Adult Royal Spoonbill with nuptial plumes at nest. The male and female look the same and both share in incubation and raising the young.

Royal Spoonbill nest with three eggs – note the leg of a young Ibis on the upper edge of the nest.

 The bird soon returned to the nest and resumed incubation.

Two spoonbills at nests on the Ibis rookery with one bird settled on the nest, presumably incubating eggs at this stage.     
Another bird incubating and sleeping at the same time.

The Spoonbills must share the nesting site with the Ibis. 

The Spoonbills have started their breeding late in the Ibis breeding cycle, with eggs still being incubated at a time when the Ibis young are well advanced. It is likely that the spoonbill young will hatch out and grow when the Ibis have left the rookery.

Without the protection of a bigger group, the young Spoonbills will be very vulnerable to the raptor predators now gathered in large numbers for the Ibis breeding event. I will watch the Spoonbills with interest and concern and hope they can successfully raise a new generation of Royal Spoonbills this breeding season.

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